Download or read book Dynamics of Tropical African Climate and Marine Sediment During Major Climate Transition written by Olubunmi Eniola and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents the late Miocene/early Pliocene climate transition (7-5 Ma) as recorded in marine sediments from Ocean Drilling Programme (ODP) Site 959 in the equatorial Atlantic off tropical West Africa, and a reconstruction of changing Holocene environments of the Eastern Tropical Atlantic (CHEETA) based on surface and core sediments from a transect along the Portuguese and NW African margin. The late Miocene to early Pliocene climate transition had irreversible consequences for atmospheric and ocean circulation leading to global cooling, northern hemisphere glaciations and modern climate conditions. In this study, continental climate, vegetation change and surface ocean dynamics at millennial time scale resolution is investigated from U\7' alkenone derived SST, leaf wax lipids and organic carbon records (TaG). Despite low TOC "1 %) which was highly variable at cm-scale (-2.5-5 kyr) resolution, ubiquitous evidence from alkenones (C37:2 and C37:3) and leaf wax lipids indicate that the primary climate signal was preserved. The UK3y' based SST estimates (24.8-29°G) showed pronounced warm and cool cycles in the magnitude of 4°C. Elevated leaf wax lipids n-alkanes (Cn C29, and C31) correspond with cool SSTs and indicate a coupled relationship between upwelling and atmospheric ocean circulation patterns which intensified around 5.6 Ma arguing for wind driven deposition from terrestrial sources related to the position and strength of the ITCZ. The high amplitude cyclic patterns in the ODP Site 959 records were investigated by time frequency analyses. The common 41 kyr in all records supports a response to high latitude climate forcing. The 75 kyr variations and lead/lag observed in the leaf waxes and SST records during the late Miocene to early Pliocene are probably related to continental ice volume variations. The study on surface sediments from the Portuguese and NW African margins, confirm the presence of two soil-specific biomarkers, branched GDGTs (expressed as the BIT index) and bacteriohopanepolyols (BHPs), in this region of almost exclusive aeolian export. TOC exceeding 2% and 013Corg gradients from -22.5%0 off Portugal to - 19%0 off W Africa identify areas of upwelling off Cape Blanc and the transition from C3 to C4 vegetation habitats in Northern Africa, respectively. Despite low signals of the molecular records, slightly stronger response of soil-marker BHPs in the sediments is attributed to preferential erosion of the upper, (oxic) part of the soil column in central African source areas, the proposed source for soil BHPs. An alternative explanation is that in situ production of the branched GDGTs may be responsible for the low BIT index. As yet there is no evidence of the soil BHPs, adenosylhopane produced in situ in marine systems and aeolian transport of GDGTs is yet to been proven. More studies on dust samples from continental margins needs to be carried out to validate this transport mechanism of branched GDGTs and BHPs. A compilation of first bulk geochemical and molecular results from a selection of cores from the Portuguese and NW African margin within an integrated chronological framework document the variations in marine sedimentation and constrain regional variations in continental climate and terrigenous supply since the last glacial period. TOC accumulation records document millennial scale variability in response to the African Humid Period. Carbon isotope trends pronounced during the last glacial maximum support organic matter input from C4 type vegetation during colder glacial periods. Preliminary molecular isotopic records of n-alkanes identify gaps in this study that will need further investigation to assess and confirm vegetation sources and continental climatic conditions over Northwest Africa.

Download or read book Dynamics of Tropical African Climate and Marine Sedimentation During Major Climate Transitions written by Olubunmi Eniola and published by . This book was released on 2011 with total page 229 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Meteorology and Climate of Tropical Africa written by Marcel Leroux and published by Springer Science & Business Media. This book was released on 2001-09-01 with total page 604 pages. Available in PDF, EPUB and Kindle. Book excerpt: This unique book includes 250 maps related to various factors of meteorology and climate and their effects on the African continent. It provides detailed coverage of fundamentally important issues concerning African meterology, climatology, tropical circulation, rainfall, drought and climate change.

Download or read book African Climate and Climate Change written by Charles J. R. Williams and published by Springer Science & Business Media. This book was released on 2011-02-11 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: Compared to many other regions of the world, Africa is particularly vulnerable to the effects of climate change and variability. Widespread poverty, an extensive disease burden and pockets of political instability across the continent has resulted in a low resilience and limited adaptative capacity of African society to climate related shocks and stresses. To compound this vulnerability, there remains large knowledge gaps on African climate, manifestations of future climate change and variability for the region and the associated problems of climate change impacts. Research on the subject of African climate change requires an interdisciplinary approach linking studies of environmental, political and socio-economic spheres. In this book we use different case studies on climate change and variability in Africa to illustrate different approaches to the study of climate change in Africa from across the spectrum of physical, social and political sciences. In doing so we attempt to highlight a toolbox of methodologies (along with their limitations and advantages) that may be used to further the understanding of the impacts of climate change in Africa and thus help form the basis for strategies to negate the negative implications of climate change on society.

Download or read book Tropical and sub tropical West Africa Marine and continental changes during the Late Quaternary written by P. Giresse and published by Elsevier. This book was released on 2007-11-30 with total page 407 pages. Available in PDF, EPUB and Kindle. Book excerpt: West Africa and the eastern Atlantic stretching from Mauritania in the north to Namibia in the south offer a large latitudinal stretch incorporating nearly symmetrical climatic gradients from the Equator. On the time scale of Quaternary Glacial and Interglacial cycles, today, we possess well-documented and recently published marine sedimentary records showing changes in oceanic and atmospheric circulations and terrestrial fluxes. Deep-sea sediment records contain a wide range of palaeoenvironmental indicators like oxygen and carbon isotopes, alkenones, foraminiferal and other planktonic assemblages over time periods up to and greater than 125,000 years. These are signals of temperature and circulation shifts and allow Interglacial and Glacial comparisons on a regional and inter-hemispheric scale. However, this effort to synthesize the existing knowledge cannot yet aspire to a global modelling. Linking with terrestrial records, albeit spatially patchy and generally lacking a firm chronology, this book points to shorter time scale chronologies from lakes, marshes and river deposits. Diverse and not very wellknown literature, both French and English, is reported here. Lastly, the book records recent knowledge of the first steps of human occupation of frequently hostile environments and considers the environmental impact of ancient and modern societies.* Covers the recent studies about marine Quaternary environments off West Africa, as well as continental Quaternary environments of tropical and sub-tropical West Africa (over 10,000 to 100,000 years)* Compares the parallel between palae-oenvironmental trends according to latitudinal gradients

Download or read book Climate Change and Cultural Dynamics written by David G. Anderson and published by Elsevier. This book was released on 2011-07-28 with total page 603 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Middle Holocene epoch (8,000 to 3,000 years ago) was a time of dramatic changes in the physical world and in human cultures. Across this span, climatic conditions changed rapidly, with cooling in the high to mid-latitudes and drying in the tropics. In many parts of the world, human groups became more complex, with early horticultural systems replaced by intensive agriculture and small-scale societies being replaced by larger, more hierarchial organizations. Climate Change and Cultural Dynamics explores the cause and effect relationship between climatic change and cultural transformations across the mid-Holocene (c. 4000 B.C.). - Explores the role of climatic change on the development of society around the world - Chapters detail diverse geographical regions - Co-written by noted archaeologists and paleoclimatologists for non-specialists

Download or read book Interacting Climates of Ocean Basins written by Carlos R. Mechoso and published by Cambridge University Press. This book was released on 2020-11-26 with total page 359 pages. Available in PDF, EPUB and Kindle. Book excerpt: Climate variability in different ocean basins can impact one another, for instance the El Niño/Southern Oscillation (ENSO) in the Pacific Ocean has remote effects on other tropical oceans around the world, which in turn modulate ENSO. With chapters by eminent researchers, this book provides a comprehensive review on how interactions among the climates in different ocean basins are key contributors to global climate variability. It discusses how interbasin interactions are mediated by oceanic and atmospheric bridges and explains exciting new possibilities for enhancing climate prediction globally. The first part of the book covers essential theory and introduces the basic mechanisms for remote connection and local amplification. The second presents outstanding examples. The latter part discusses applications to cases of societal interest such as impacts on monsoon systems and expectations after climate change. This comprehensive reference is a useful resource for graduate students and researchers in the atmospheric and ocean sciences.

Download or read book Quaternary Vegetation Dynamics written by Jürgen Runge and published by CRC Press. This book was released on 2021-11-28 with total page 412 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book celebrates the relaunch of the African Pollen Database, presents state-of-the-art of modern and ancient pollen data from sub-Saharan Africa, and promotes Open Access science. Pollen grains are powerful tools for the study of past vegetation dynamics because they preserve well within sedimentary deposits and have a huge diversity in ornamentation that allows different taxa to be determined. The reconstruction of past vegetation from the examination of ancient pollen records thus can be used to characterize the nature of past landscapes (e.g. abundance of forests vs. grasslands), provide insights into changes in biodiversity, and gain empirical evidence of vegetation response to climatic change and human activity. In this, the 35th Volume of "Palaeoecology of Africa", we bring together new data and extensive synthetic reviews to provide novel insights into the relationships between human evolution, human activity, climate change and vegetation dynamics during the Quaternary, the last 2.6 million years. Current and ongoing climate and land-use change is exerting pressure on modern vegetation formations and threatening the livelihoods and wellbeing of many peoples in Africa. In this book the focus is on the Quaternary because it is during this geological period that the modern vegetation formations developed into their current configurations against a backdrop of high magnitude global climate change (glacial-interglacial cycles), human evolution, and a growing human land-use footprint. In this book the latest information is presented and collated from around the African continent to parameterize past vegetation states, identify the drivers of vegetation change, and assess the vegetation resilience to change. To achieve this research from two broad themes are covered: (i) the present is the key to the past (i.e. studies which improve our understanding of modern environments so that we can better interpret evidence from the past), and (ii) the past is the key to the future (i.e. studies which unlock information on how and why vegetation changed in the past so one can better anticipate trajectories of future change). This Open Access book will provide a strong foundation for future research exploring past ecological, environmental and climatic change within Africa and the surrounding islands. The book is organized regionally (covering western, eastern, central, and southern Africa) and it contains specialized articles focused on particular topics (such as modern pollen-vegetation relationships and fire as a driver of vegetation change), as well as regional and pan-African syntheses drawing together decades of research to assess key scientific questions (including the role of climate in driving vegetation change and the role of vegetation change in human evolution). These articles will be useful to students and teachers from high school to the highest level of university who are interested in the origins and dynamics of vegetation in Africa. Furthermore, it is also meant to provide societally relevant information that can act as an inspiration for the development of sustainable management practices for the future.

Download or read book The Ocean and Cryosphere in a Changing Climate written by Intergovernmental Panel on Climate Change (IPCC) and published by Cambridge University Press. This book was released on 2022-04-30 with total page 755 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Intergovernmental Panel on Climate Change (IPCC) is the leading international body for assessing the science related to climate change. It provides policymakers with regular assessments of the scientific basis of human-induced climate change, its impacts and future risks, and options for adaptation and mitigation. This IPCC Special Report on the Ocean and Cryosphere in a Changing Climate is the most comprehensive and up-to-date assessment of the observed and projected changes to the ocean and cryosphere and their associated impacts and risks, with a focus on resilience, risk management response options, and adaptation measures, considering both their potential and limitations. It brings together knowledge on physical and biogeochemical changes, the interplay with ecosystem changes, and the implications for human communities. It serves policymakers, decision makers, stakeholders, and all interested parties with unbiased, up-to-date, policy-relevant information. This title is also available as Open Access on Cambridge Core.

Download or read book The African Neogene Climate Environments and People written by Jürgen Runge and published by CRC Press. This book was released on 2017-10-12 with total page 224 pages. Available in PDF, EPUB and Kindle. Book excerpt: During the Neogene – covering the last 23 Million years – the evolution of the environmental setting in Africa was subject to considerable changes. Natural shifts, slow and rapid, evidenced by modifications in palaeogeography, geodynamics, climate, and vegetation have caused repeated and strong changes of ecosystems in the lower latitudes. Using a variety of proxy data – researched and applied by many authors from numerous disciplines – an attempt is made to reconstruct African landscapes over space and time. Besides such spatio-temporal oscillations in recently humid, semi-humid, and dry areas of Africa, this volume of Palaeoecology of Africa (PoA) focuses on long term interrelationships between ecosystem dynamics and climate change, not ignoring the ever growing and ongoing influence of humans on natural ecosystems since the Quaternary. Regionally, this volume lays a strong focus on Nigeria (Niger Delta). Facing the omnipresent challenges of Global Change, an increasing number of African scientists is involved in palaeoenvironmental and palaeoclimatic research, both theoretical and applied. PoA systematically supports established as well as junior African scientists in the field of sustainable cooperation and academic capacity building. This book will be of interest to all concerned with or interested in up-to-date research on Neogene to Quaternary low latitudes ecosystem changes and their respective interpretation in the framework of natural climate and vegetation change evidenced by a variety of methods that allow to read and learn from the past by following the motto, "The geologic foretime as the key to the present, and possibly to the future." Palynologists, Geologists, Geographers, Archaeologists, and Geomorphologists will find this edition equally useful for their work.

Download or read book Climate Change and Africa written by Pak Sum Low and published by Cambridge University Press. This book was released on 2006-11-02 with total page 413 pages. Available in PDF, EPUB and Kindle. Book excerpt: At the beginning of the twenty-first century, no environmental issue is of such truly global magnitude as the issue of climate change. The poorer, developing countries are the least equipped to adapt to the potential effects of climate change, although most of them have played an insignificant role in causing it. African countries are amongst the poorest of the developing countries. This book presents the issues of most relevance to Africa, such as past and present climate, desertification, biomass burning and its implications for atmospheric chemistry and climate, energy generation, sea-level rise, ENSO-induced drought and flood, adaptation, disaster risk reduction, the UNFCCC and Kyoto Protocol (especially the Clean Development Mechanism), capacity-building, and sustainable development. It provides a comprehensive and up-to-date review of these and many other issues, with chapters by the leading experts from a range of disciplines. Climate Change and Africa will prove to be an invaluable reference for all researchers and policy makers with an interest in climate change and Africa.

Download or read book Ice Ages Climate Dynamics and Biotic Events The Late Pennsylvanian World written by S.G. Lucas and published by Geological Society of London Special Publications. This book was released on 2023-06-19 with total page 505 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Late Pennsylvanian was a time of ice ages and associated climate dynamics. A major reduction in Gondwana ice-volume was followed by a prolonged period of relative global warmth, culminating in the last great ice age of the late Paleozoic. It also was a major turning point in the evolution of life on land, when the coal forests of the Middle Pennsylvanian gave way to new kinds of Late Pennsylvanian wetland vegetation, and new kinds of animals appeared. Changes in the terrestrial biota began during the Middle Pennsylvanian, accelerating and proceeding in a spatially complex manner throughout the Late Pennsylvanian. The Late Pennsylvanian is thus a laboratory for studying environmental changes in a glacial world, and for assessing coeval biotic changes, in part to establish the possible links between the two. No book has been dedicated to this time interval, so this volume fills a gap in our understanding of a dynamic Late Pennsylvanian world that is much like the late Cenozoic world.

Download or read book The Climate of Tropical and Northern Africa written by Heiko Paeth and published by . This book was released on 2005 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Oceanography Climate and Vegetation Development of Tropical Africa During the Last Glacial written by Ines Heßler and published by . This book was released on 2011 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Influence of the Sea Surface Temperature Decadal Variability on Tropical Precipitation West African and South American Monsoon written by Julián Villamayor and published by Springer. This book was released on 2019-07-05 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book the Sea Surface Temperature (SST) patterns of decadal-to-multidecadal variability observed and simulated by 17 general circulation models (GCMs) are analyzed. Furthermore, their impact on precipitation in West Africa and South America and the atmospheric mechanisms involved are assessed. Through this analysis, the effect of external forcings on these impacts and the relative contribution of decadal-to-multidecadal variability patterns of SST to precipitation are presented in depth. Finally, a humid period in the West African region of the Sahel during the 19th century, previously little documented, is analyzed using an atmospheric GCM. The monsoons of West Africa and South America have shown changes in the timescales of a few decades. Previous work suggests a relationship with patterns of decadal-to-multidecadal variability of SST, such as global warming and the Atlantic and Pacific variability. However, the dynamics underlying this relationship and its simulation by current GCMs had not been addressed in a consistent manner. This is the main motivation of this book. The results of this book not only represent a great step forward in our understanding of the changes in the precipitation regimes of the studied regions, but they can also be of great help for the improvement of decadal prediction systems and the associated social consequences.

Download or read book The First Humans written by Frederick E. Grine and published by Springer Science & Business Media. This book was released on 2009-05-24 with total page 217 pages. Available in PDF, EPUB and Kindle. Book excerpt: There are some issues in human paleontology that seem to be timeless. Most deal with the origin and early evolution of our own genus – something about which we should care. Some of these issues pertain to taxonomy and systematics. How many species of Homo were there in the Pliocene and Pleistocene? How do we identify the earliest members the genus Homo? If there is more than one Plio-Pleistocene species, how do they relate to one another, and where and when did they evolve? Other issues relate to questions about body size, proportions and the functional adaptations of the locomotor skeleton. When did the human postcranial “Bauplan” evolve, and for what reasons? What behaviors (and what behavioral limitations) can be inferred from the postcranial bones that have been attributed to Homo habilis and Homo erectus? Still other issues relate to growth, development and life history strategies, and the biological and archeological evidence for diet and behavior in early Homo. It is often argued that dietary change played an important role in the origin and early evolution of our genus, with stone tools opening up scavenging and hunting opportunities that would have added meat protein to the diet of Homo. Still other issues relate to the environmental and climatic context in which this genus evolved.

Download or read book Climate Change and Marine Geological Dynamics written by George Kontakiotis and published by Mdpi AG. This book was released on 2021-11-11 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: The tendency for climate to change has been one of the most surprising outcomes of the study of Earth's history. Marine geoscience can reveal valuable information about past environments, climates, and biota just before, during and after each climate perturbation. Particularly, certain intervals of geological records are windows to key episodes in the climate history of the Earth-life system. Ιn this regard, the detailed analyses of such time intervals are challenging and rewarding for environmental reconstruction and climate modelling, because they provide documentation and better understanding of a warmer-than-present world, and opportunities to test and refine the predictive ability of climate models. Marine geological dynamics such as sea-level changes, hydrographic parameters, water quality, sedimentary cyclicity, and (paleo)climate are strongly related through a direct exchange between the oceanographic and atmospheric systems. The increasing attention paid to this wide topic is also motivated by the interplay of these processes across a variety of settings (coastal to open marine) and timescales (early Cenozoic to modern). In order to realize the full predictive value of these warm (fresh)/cold (salty) intervals in Earth's history, it is important to have reliable tools (e.g., integrated geochemical, paleontological and/or paleoceanographic proxies) through the application of multiple, independent, and novel techniques (e.g., TEX86, UK'37, Mg/Ca, Na/Ca, Δ47, and μCT) for providing reliable hydroclimate reconstructions at both local and global scales.